At present, most websites or forums require users to enter a verification code when registering, logging in, posting, replying, downloading a file and purchasing goods or services. Verification codes are mainly used to identify whether they are real user behaviors or malicious behaviors. Most of the existing verification code technologies randomly generate numbers or letters and display them to users in the form of pictures. In order to increase the difficulty of machine cracking, the interference bars (codes), distorted and curved picture elements and various nesting algorithms and so on are used in the verification code picture. These methods, to a certain extent, increase the difficulty of customer's recognition, and are easy to arouse an averse mentality of users.
On the one hand, some advertisers utilize the verification codes frequently displayed to advertise by means of many new methods. However, the effect of advertising by adding the verification codes into the advertisements is not good in reality. On the other hand, nesting random codes as verification codes in advertisements not only undermines the overall effects of the advertisements, but also makes the content of the advertisements easy to be ignored by users.
Therefore, a suitable verification method is needed. The suitable verification method will not only be difficult to crack technically but also satisfy various aspects demands of publicity by combining the advertisements, thereby increasing the social benefits.